LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 58

Search options

  1. Article: Sodium hypochlorite as an oxidizing agent for removal of soil organic matter before microplastics analyses

    Bottone, Anna / Boily, Jean‐Francois / Shchukarev, Andrey / Andersson, Patrik L. / Klaminder, Jonatan

    Journal of environmental quality. 2022 Jan., v. 51, no. 1

    2022  

    Abstract: The omnipresence of microplastics (MPs) across Earth's surface has raised concerns about their environmental impact and created an urgent need for methods to identify them in complex soil and sedimentary matrices. However, detecting MPs in the O horizons ...

    Abstract The omnipresence of microplastics (MPs) across Earth's surface has raised concerns about their environmental impact and created an urgent need for methods to identify them in complex soil and sedimentary matrices. However, detecting MPs in the O horizons of soils is difficult because plastic polymers share many physical and chemical properties with natural soil organic matter (SOM). In this study, we assessed whether sodium hypochlorite (NaOCl), a reagent that can oxidize SOM and simultaneously preserve mineral constituents, can be used for MP analysis and characterization in soil environments. In addition, we scrutinized how factors such as MP size, polymer type, extraction methods, and soil matrix affect the recovery of microplastic particles. We used both hydrophobic and density‐dependent separation methods to assess the effects of our oxidation treatment on the recovery of MP. We observed that NaOCl effectively removed SOM without greatly altering the surface properties of resistant MP polymers (polypropylene, polylactic acid, low‐density polyethylene, and polyethylene terephthalate), which were characterized using scanning electron microscopy and Fourier‐transform infrared spectroscopy after SOM removal. The NaOCl treatment caused some chlorination and formation of additional C–OH bonds on polymer surfaces, which likely contributed to the reduced efficiency of the hydrophobic‐based (oil) extraction. We conclude that NaOCl treatment can improve detection of MPs in SOM‐rich soil and that recovery of MPs from soils is influenced by MP size, polymer type, extraction method, and soil type, which makes it challenging to develop a universal analytical method.
    Keywords Fourier transform infrared spectroscopy ; chlorination ; environmental impact ; environmental quality ; hydrophobicity ; microplastics ; oils ; oxidation ; polyethylene ; polyethylene terephthalates ; polylactic acid ; polypropylenes ; sodium hypochlorite ; soil organic matter ; soil types
    Language English
    Dates of publication 2022-01
    Size p. 112-122.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 120525-0
    ISSN 1537-2537 ; 0047-2425
    ISSN (online) 1537-2537
    ISSN 0047-2425
    DOI 10.1002/jeq2.20321
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  2. Article: Cryogenic X-ray photoelectron spectroscopy determines surface composition of algal cells and gives insights into their spontaneous sedimentation

    Gojkovic, Zivan / Shchukarev, Andrey / Ramstedt, Madeleine / Funk, Christiane

    Algal research. 2020 May, v. 47

    2020  

    Abstract: The flotation properties of two green microalgal species isolated from Northern Sweden, Chlorella vulgaris 13-1 and Coelastrella sp. 3-4, were investigated. C. vulgaris 13-1 is a flotating alga that remains suspended in solution during culturing, while ... ...

    Abstract The flotation properties of two green microalgal species isolated from Northern Sweden, Chlorella vulgaris 13-1 and Coelastrella sp. 3-4, were investigated. C. vulgaris 13-1 is a flotating alga that remains suspended in solution during culturing, while Coelastrella sp. 3-4 is readily sedimenting in the stationary growth phase. We were the first to use cryogenic X-ray photoelectron spectroscopy (Cryo-XPS) to gain information on the chemical composition of the algal cell surface and added to these data results obtained from diffuse reflectance - Fourier Transform infrared spectroscopy (DR-FTIR) and classical chemical extractions of carbohydrates, lipids and proteins.Based on the Cryo-XPS data the surface of the sedimenting Coelastrella sp. 3-4 strain is rich in proteins and lipids, while the cell surface of non-flocculating C. vulgaris 13-1 is predominated by carbohydrates, but is poor in lipids. The Zeta-potential of both strains was equally negative. Cell size and the amount of carbohydrates on the algal cell surface, but not the negative surface charge, therefore indicate colloidal stability of microalgae in solutions and can be applied to predict flotation properties of green microalgae.
    Keywords Chlorella vulgaris ; Fourier transform infrared spectroscopy ; X-ray photoelectron spectroscopy ; carbohydrates ; chemical composition ; developmental stages ; lipids ; microalgae ; proteins ; reflectance ; reflectance spectroscopy ; zeta potential ; Sweden
    Language English
    Dates of publication 2020-05
    Publishing place Elsevier B.V.
    Document type Article
    ISSN 2211-9264
    DOI 10.1016/j.algal.2020.101836
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  3. Article ; Online: Sodium hypochlorite as an oxidizing agent for removal of soil organic matter before microplastics analyses.

    Bottone, Anna / Boily, Jean-Francois / Shchukarev, Andrey / Andersson, Patrik / Klaminder, Jonatan

    Journal of environmental quality

    2022  Volume 51, Issue 1, Page(s) 112–122

    Abstract: The omnipresence of microplastics (MPs) across Earth's surface has raised concerns about their environmental impact and created an urgent need for methods to identify them in complex soil and sedimentary matrices. However, detecting MPs in the O horizons ...

    Abstract The omnipresence of microplastics (MPs) across Earth's surface has raised concerns about their environmental impact and created an urgent need for methods to identify them in complex soil and sedimentary matrices. However, detecting MPs in the O horizons of soils is difficult because plastic polymers share many physical and chemical properties with natural soil organic matter (SOM). In this study, we assessed whether sodium hypochlorite (NaOCl), a reagent that can oxidize SOM and simultaneously preserve mineral constituents, can be used for MP analysis and characterization in soil environments. In addition, we scrutinized how factors such as MP size, polymer type, extraction methods, and soil matrix affect the recovery of microplastic particles. We used both hydrophobic and density-dependent separation methods to assess the effects of our oxidation treatment on the recovery of MP. We observed that NaOCl effectively removed SOM without greatly altering the surface properties of resistant MP polymers (polypropylene, polylactic acid, low-density polyethylene, and polyethylene terephthalate), which were characterized using scanning electron microscopy and Fourier-transform infrared spectroscopy after SOM removal. The NaOCl treatment caused some chlorination and formation of additional C-OH bonds on polymer surfaces, which likely contributed to the reduced efficiency of the hydrophobic-based (oil) extraction. We conclude that NaOCl treatment can improve detection of MPs in SOM-rich soil and that recovery of MPs from soils is influenced by MP size, polymer type, extraction method, and soil type, which makes it challenging to develop a universal analytical method.
    MeSH term(s) Environmental Monitoring ; Microplastics ; Oxidants ; Plastics ; Sodium Hypochlorite ; Soil ; Water Pollutants, Chemical
    Chemical Substances Microplastics ; Oxidants ; Plastics ; Soil ; Water Pollutants, Chemical ; Sodium Hypochlorite (DY38VHM5OD)
    Language English
    Publishing date 2022-01-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 120525-0
    ISSN 1537-2537 ; 0047-2425
    ISSN (online) 1537-2537
    ISSN 0047-2425
    DOI 10.1002/jeq2.20321
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Analysis of Bacterial Cell Surface Chemical Composition Using Cryogenic X-Ray Photoelectron Spectroscopy.

    Ramstedt, Madeleine / Shchukarev, Andrey

    Methods in molecular biology (Clifton, N.J.)

    2016  Volume 1440, Page(s) 215–223

    Abstract: This chapter describes a method for measuring the average surface chemical composition with respect to lipids, polysaccharides, and peptides (protein + peptidoglycan) for the outer part of the bacterial cell wall. Bacterial cultures grown over night are ... ...

    Abstract This chapter describes a method for measuring the average surface chemical composition with respect to lipids, polysaccharides, and peptides (protein + peptidoglycan) for the outer part of the bacterial cell wall. Bacterial cultures grown over night are washed with a buffer or saline at controlled pH. The analysis is done on fast-frozen bacterial cell pellets obtained after centrifugation, and the analysis requires access to X-ray photoelectron spectroscopy instrumentation that can perform analyses at cryogenic temperatures (for example using liquid nitrogen). The method can be used to monitor changes in the cell wall composition following environmental stimuli or genetic mutations. The data obtained originate from the outermost part of the cell wall. Thus, it is expected that for gram-negative bacteria only the outer membrane and part of the periplasmic peptidoglycan layer is probed during analysis, and for gram-positive bacteria only the top nanometers of the peptidoglycan layer of the cell wall is monitored.
    Language English
    Publishing date 2016
    Publishing country United States
    Document type Journal Article
    ISSN 1940-6029
    ISSN (online) 1940-6029
    DOI 10.1007/978-1-4939-3676-2_16
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article: Applying Cryo-X-ray Photoelectron Spectroscopy to Study the Surface Chemical Composition of Fungi and Viruses.

    Shchukarev, Andrey / Backman, Emelie / Watts, Samuel / Salentinig, Stefan / Urban, Constantin F / Ramstedt, Madeleine

    Frontiers in chemistry

    2021  Volume 9, Page(s) 666853

    Abstract: Interaction between microorganisms and their surroundings are generally ... ...

    Abstract Interaction between microorganisms and their surroundings are generally mediated
    Language English
    Publishing date 2021-05-28
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2711776-5
    ISSN 2296-2646
    ISSN 2296-2646
    DOI 10.3389/fchem.2021.666853
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article ; Online: Cobalt-doped hematite thin films for electrocatalytic water oxidation in highly acidic media.

    Kwong, Wai Ling / Lee, Cheng Choo / Shchukarev, Andrey / Messinger, Johannes

    Chemical communications (Cambridge, England)

    2019  Volume 55, Issue 34, Page(s) 5017–5020

    Abstract: Earth-abundant cobalt-doped hematite thin-film electrocatalysts were explored for acidic water oxidation. The strategically doped hematite produced a stable geometric current density of 10 mA cm-2 for up to 50 h at pH 0.3, as a result of Co-enhanced ... ...

    Abstract Earth-abundant cobalt-doped hematite thin-film electrocatalysts were explored for acidic water oxidation. The strategically doped hematite produced a stable geometric current density of 10 mA cm-2 for up to 50 h at pH 0.3, as a result of Co-enhanced intrinsic catalytic activity and charge transport properties across the film matrix.
    Language English
    Publishing date 2019-04-10
    Publishing country England
    Document type Journal Article
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/c9cc01369e
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article: Cryo-XPS – A new technique for the quantitative analysis of the structure of electric double layer at colloidal particles?

    Škvarla, Jiří / Kaňuchová, Mária / Shchukarev, Andrey / Girová, Anna / Brezáni, Ivan

    Colloids and surfaces. 2020 Feb. 05, v. 586

    2020  

    Abstract: There is a long-lasting uncertainty as to the structure of the metal oxide/water interface. Various structures have especially been invoked to rationalize the seemingly anomalous silica/water interface. But, none of them seems to be approved in a ... ...

    Abstract There is a long-lasting uncertainty as to the structure of the metal oxide/water interface. Various structures have especially been invoked to rationalize the seemingly anomalous silica/water interface. But, none of them seems to be approved in a quantitative and systematic way. We show that the concentration ratio of monovalent counterions and coions around colloidal silica spheres, as detected by the cryo-XPS technique, follows fundamental theoretical predictions of either Boltzmann or Donnan distribution. It is suggested that the reason of the dual response is the formation of the swelling gel layer on the silica surface due to its longer contact with water.
    Keywords colloids ; gels ; prediction ; quantitative analysis ; silica ; uncertainty
    Language English
    Dates of publication 2020-0205
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1500517-3
    ISSN 0927-7757
    ISSN 0927-7757
    DOI 10.1016/j.colsurfa.2019.124234
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  8. Article ; Online: Electrografting of 4-Carboxybenzenediazonium on Glassy Carbon Electrode: The Effect of Concentration on the Formation of Mono and Multilayers.

    Phal, Sereilakhena / Shimizu, Kenichi / Mwanza, Daniel / Mashazi, Philani / Shchukarev, Andrey / Tesfalidet, Solomon

    Molecules (Basel, Switzerland)

    2020  Volume 25, Issue 19

    Abstract: Grafting of electrodes with diazonium salts using cyclic voltammetry (CV) is a well-established procedure for surface modification. However, little is known about the effect of the concentration of the diazonium salt on the number of layers grafted on ... ...

    Abstract Grafting of electrodes with diazonium salts using cyclic voltammetry (CV) is a well-established procedure for surface modification. However, little is known about the effect of the concentration of the diazonium salt on the number of layers grafted on the electrode surface. In this work, the impact of concentration on the grafting of 4-carboxybenzenediazonium (4-CBD) onto a glassy carbon electrode (GCE) is elucidated. The number of layers grafted on the GCE was linearly dependent on the concentration of 4-CBD and varied between 0.9 and 4.3 when the concentration was varied between 0.050 and 0.30 mmol/L at 0.10 V.s
    MeSH term(s) Borates/chemistry ; Carbon/chemistry ; Electrochemistry/methods ; Electrodes ; Oxidation-Reduction
    Chemical Substances Borates ; Carbon (7440-44-0) ; fluoroboric acid (H429WZ9FBQ)
    Language English
    Publishing date 2020-10-07
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules25194575
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article ; Online: Cryo-XPS for Surface Characterization of Nanomedicines.

    Cant, David J H / Pei, Yiwen / Shchukarev, Andrey / Ramstedt, Madeleine / Marques, Sara S / Segundo, Marcela A / Parot, Jeremie / Molska, Alicja / Borgos, Sven E / Shard, Alexander G / Minelli, Caterina

    The journal of physical chemistry. A

    2023  Volume 127, Issue 39, Page(s) 8220–8227

    Abstract: Nanoparticles used for medical applications commonly possess coatings or surface functionalities intended to provide specific ... ...

    Abstract Nanoparticles used for medical applications commonly possess coatings or surface functionalities intended to provide specific behavior
    MeSH term(s) Nanomedicine ; Polyethylene Glycols/chemistry ; Drug Delivery Systems ; Nanoparticles/chemistry ; Polymers
    Chemical Substances Polyethylene Glycols (3WJQ0SDW1A) ; Polymers
    Language English
    Publishing date 2023-09-21
    Publishing country United States
    Document type Journal Article
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/acs.jpca.3c03879
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  10. Article ; Online: X-ray Photoelectron Spectroscopy of Fast-Frozen Hematite Colloids in Aqueous Solutions. 6. Sodium Halide (F

    Lucas, Marie / Yeşilbaş, Merve / Shchukarev, Andrey / Boily, Jean-François

    Langmuir : the ACS journal of surfaces and colloids

    2018  Volume 34, Issue 45, Page(s) 13497–13504

    Abstract: Electrolyte ion binding at mineral surfaces is central to the generation of surface charge and key to electric double-layer formation. X-ray photoelectron spectroscopy of fast-frozen (-170 °C) mineral wet pastes provides a means to study weakly bound ... ...

    Abstract Electrolyte ion binding at mineral surfaces is central to the generation of surface charge and key to electric double-layer formation. X-ray photoelectron spectroscopy of fast-frozen (-170 °C) mineral wet pastes provides a means to study weakly bound electrolyte ions at the mineral/water interface. In this study, we build upon a series of articles devoted to ion binding at hematite (α-Fe
    Language English
    Publishing date 2018-10-31
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2005937-1
    ISSN 1520-5827 ; 0743-7463
    ISSN (online) 1520-5827
    ISSN 0743-7463
    DOI 10.1021/acs.langmuir.8b01507
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top